(a) Field of the Invention
This invention relates to an improvement in or relating to a carrier for supporting a single lot of prescribed sheets of semiconductor wafers from one processing of treatment step to another in their cleaning and etching processing or treatment. More particularly, it relates to such a wafer-supporting carrier as mentioned above, which is provided with an information member, for example, an information card containing a semiconductor chip which in turn constitutes a microprocessor and memory.
(b) Description of the Prior Art
The cleaning and etching processing or treatment (hereinafter referred simply to "cleaning and etching processing") generally consists of 100-200 processing steps. Semiconductor wafers are supported on a carrier as a single lot of 25-50 sheets and successively transferred from one processing step to another so as to subject them to prescribed processing or treatment. The control of each processing step has heretofore been carried out in accordance with the mannual control system, which is dependent on process control cards, or the computerized control system which makes use of punched cards. In the former system, process information are added to process control cards by hand-writing. The latter system uses key punching machines as terminal equipment. Irrespective of the systems, the prior art system are accompanied by a drawback that no satisfactory collation is available due to lack of correctness. Furthermore, it is rather difficult to automate the overall processing or treatment with such prior art systems. Even if the processing or treatment should be automated, all instructions cannot help depending on human operators so that instruction errors are thus unavoidable. In addition, the prior art systems are accompanied by the production of rubbish since process control cards are made of paper. This has been a serious problem particularly for wafers because wafers are to be used for the fabrication of super precision parts. They are also accompanied by another problem that such control cards or punched cards do not permit the writing-in of problems which their respective wafer encounter during processing or treatment or any other things which operators notice upon carrying out the processing or treatment.